NO.12 LOW IDLE/STALLS DURING DECELERATION [MZR-CD (RF Turbo)]
id0103f1821000
12 |
LOW IDLE/STALLS DURING DECELERATION |
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DESCRIPTION
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• Engine stops unexpectedly at the beginning of deceleration or recovery from deceleration.
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POSSIBLE CAUSE
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• Intake-air system restriction or clogging
• Poor fuel quality
• A/C system improper operation
• Inadequate fuel pressure
• Suction control valve malfunction (built-in supply pump)
• Fuel pressure limiter malfunction (built-in common rail)
• Fuel leakage
• Fuel line restriction or clogging
• Fuel filter restriction or clogging
• Incorrect fuel injection timing
• Incorrect idle speed
• Erratic signal from CKP sensor
• Erratic signal from CMP sensor
• Supply pump malfunction
• Fuel injector malfunction
• Low engine compression
• Improper valve timing
• Glow system malfunction
• EGR system malfunction
• MAF/IAT sensor or related circuit malfunction
• ECT sensor or related circuit malfunction
• Fuel pressure sensor or related circuit malfunction
• Neutral switch malfunction or related circuit malfunction
• Accelerator pedal position (APP) sensor or related circuit malfunction
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Diagnostic Procedure
STEP |
INSPECTION |
RESULTS |
ACTION |
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1
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Does the engine idle roughly?
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Yes
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Go to the symptom troubleshooting “NO.10 ENGINE RUNS ROUGH/ROLLING IDLE [MZR-CD (RF-Turbo)]”.
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No
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Go to the next step.
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2
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Inspect the following:
• Fuel line/fuel filter clogging or restriction
• Intake-air system restriction or clogging
• Fuel quality (e.g.: include water contamination, winter/summer blend)
Are all items normal?
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Yes
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Go to the next step.
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No
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Service if necessary.
Repeat Step 2.
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3
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Perform the self-test function using the M-MDS.
Turn the engine switch to the ON position.
Retrieve any DTCs.
Are any DTCs displayed?
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Yes
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DTC is displayed:
Go to the appropriate DTC test.
Communication error message is displayed:
Inspect the following:
• Open circuit between PCM control relay and PCM terminal 119 or 120
• Open circuit PCM control relay and PCM terminal 105
• PCM control relay stuck open
• Open or poor ground circuit (PCM terminal 1, 2, 3, 114 or 117)
• Poor connection to vehicle body ground
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No
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No DTC is displayed:
Go to the next step.
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4
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Inspect idle speed.
Is the idle speed correct?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning part according to the idle speed inspection results.
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5
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Inspect the APP sensor.
Is the APP sensor normal?
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Yes
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Go to the next step.
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No
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Replace the accelerator pedal component.
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6
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Measure the voltage at PCM terminal 109 and 110.
Is voltage normal?
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Yes
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Go to the next step.
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No
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PCM terminal 109 is not as specified:
Inspect the clutch switch and related wiring harness.
PCM terminal 110 is not as specified:
Inspect the neutral switch and related wiring harness.
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7
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Visually inspect the CKP sensor and the teeth of the pulse wheel.
Are the CKP sensor and the teeth of the pulse wheel normal?
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Yes
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Go to the next step.
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No
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Replace malfunctioning parts.
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8
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Measure the gap between the CKP sensor and the teeth of the pulse wheel.
Specification
1.5—2.5 mm {0.059—0.098 in}
Is the gap within the specification?
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Yes
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Go to the next step.
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No
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Adjust the CKP sensor position.
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9
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Visually inspect the CMP sensor and the teeth of the pulse wheel.
Are the CMP sensor and the teeth of the pulse wheel normal?
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Yes
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Inspect the following PIDs:
• ECT
• IAT
• MAF
• RPM
If the PID value is not as specified, repair or replace malfunctioning parts.
If the PID value is normal, go to the next step.
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No
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Replace malfunctioning parts.
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10
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Inspect the fuel pressure sensor.
Is the fuel pressure normal?
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Yes
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Go to the next step.
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No
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Replace the common rail.
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11
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Inspect the suction control valve.
Is the suction control valve normal?
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Yes
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Go to the next step.
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No
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Replace the supply pump.
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12
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Is the engine compression correct?
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Yes
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Go to the next step.
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No
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Inspect the following:
• Damaged valve seat
• Worn valve stem and valve guide
• Worn or stuck piston ring
• Worn piston, piston ring or cylinder
• Improper valve timing
Service if necessary.
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13
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Inspect fuel injector.
Is fuel injector normal?
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Yes
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Go to the next step.
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No
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Repair or replace if necessary.
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14
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Connect the pressure gauge to A/C line.
Turn the blower and A/C switches on.
Is the pressure within specifications?
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Yes
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Go to the next step.
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No
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A/C is always on:
Go to the symptom troubleshooting “NO.26 A/C ALWAYS ON OR A/C COMPRESSOR RUNS CONTINUOUSLY [MZR-CD (RF-Turbo)]”.
Other symptoms:
Inspect the following:
• Refrigerant charging amount
• Cooling fan operation
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15
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Inspect the EGR system operation.
Is the EGR system operation normal?
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Yes
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Go to the next step.
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No
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Repair or replace the malfunctioning part according to EGR system operation results.
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16
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Inspect the glow system operation.
(See RELAY INSPECTION.)
Is glow system operation normal?
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Yes
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Remove and inspect the supply pump and common rail.
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No
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Service if necessary.
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17
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Verify test results.
• If normal, return to the diagnostic index to service any additional symptoms.
• If the malfunction remains, inspect the related Service Information and perform repair or diagnosis.
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